Summary of Significant Accounting Policies - Schedule of Effects of Reclassifications out of Accumulated Other Comprehensive Earnings (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Earnings (loss) before income taxes	$ 96,031		$ (6,554)		$ 218,822	$ 51,971
Income tax (expense) benefit	(18,379)		4,315		(42,359)	(6,287)
Net earnings (loss)	77,652	$ 98,811	(2,239)	$ 47,923	176,463	45,684
Unrealized Gains and Losses on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Net realized gains (losses) - Available-for-sale	(824)		(722)		(2,536)	(772)
Credit gains presented within net realized gains	31		303		(95)	149
Earnings (loss) before income taxes	(793)		(419)		(2,631)	(623)
Income tax (expense) benefit	167		88		553	131
Net earnings (loss)	$ (626)		$ (331)		$ (2,078)	$ (492)